Most features of program:
Proxy Checker understand TXT & HTML file formats;
Recognize different formats of proxy list (separated by colon, spaces, tabs, etc.);
Supports multi-threading (can check many proxies simultaneously);
Can check proxies for anonymity even you use Firewall;
Can check HTTP proxies for HTTPS (HTTP + SSL) support;
Can check HTTP proxies for FTP support;
Can check HTTP proxies for proxy chaining support.
Detailed description of Proxy Checker
Proxy Checker uses Internet Explorer (WinInet library) to work with Internet therefore you have a guarantee that proxies checked by Proxy Checker will work in your browser.

How to check for HTTPS support?
Just select URL begins from "https://" in "Connect to" field from "Options" sheet. All checked proxies will supports HTTPS protocol.

How to check for FTP support?
This is similar as check for HTTPS support. Just select URL begins from "ftp://" in "Connect to" field from "Options" sheet. All checked proxies will supports FTP.

How to check for proxy chaining support?
For proxy chaining support proxies must support CONNECT method. This method also needs for HTTPS therefore just check proxies for HTTPS support.

Advantages of professional version of Proxy Checker
Free version of Proxy Checker has some restrictions. If you wish you can buy professional version. This version can:

Can check any number of proxies at the same time (free version - up to 20 proxies)
Number of retries for check proxy is unlimited (free version - up to 2 retries)
Can check and save any number of proxies (free version can save up to 5000 good proxies)
Has INI file with default settings. You can easy change it.